1. Field of the Invention
This descriptive report of the invention refers to a bracket system developed to serve as an auxiliary means in orthodontic treatment, thus creating different possibilities in applied mechanics. An orthodontist may determine both its function and its relation with the wire in order to make it interactive or only passive. It is innovative because no bracket system has managed to provide these two features in the same bracket system so far. The presence of two slots which is also a significant differential feature makes various movements easier, its shape reduces discomfort reported by patients, and it is more hygienic.
2. Description of Related Art
The Boyd band bracket was the first self-ligating mechanism designed and patented by Charles E. Boyd in 1933. The Russell Lock bracket described by Stolzenberg in 1935 followed soon afterwards. The Russell Lock bracket could be opened and closed. A special key was necessary to make adjustments. Source: Berger (2011).
A little time later, James W. Ford designed the Ford adapter which was abandoned afterwards. His son began to manufacture it again in 1951. From that moment on there was big interest in this kind of self-ligating brackets, albeit without big success. A breakthrough occurred only in the 1970s, more precisely in 1971, when Alexander J. Wildman designed the Edgelock bracket (U.S. Pat. No. 3,748,740). It was a round bracket with a rigid rotating cover which passively closed the slot.
Other models followed, the main one being the Mobile lock. This concept was not well received due to its bulky design, limited control over teeth and elastic ligatures widely used by orthodontists at that time.
In the mid 70's, the SPEED bracket (U.S. Pat. No. 3,772,787), which represented the beginning of a new era for self-ligating brackets as it was an active one. But it became available on the market for the first time only in 1981.
In 1986, the Activa brackets designed by E. Pletcher (WO/1982/003979) were made available as an alternative to conventional ligation systems. Said bracket system featured a rigid circular clip that rotated in an occlusogingival direction around the cylindrical body of the bracket, thus forming a passive tube which was easily opened by a patient.
The Time bracket marketed in 1995 came next in the sequence of self-ligating bracket systems in which the clip was made from a rigid and curved material which, when closed, wrapped around the vestibular surface of the bracket body. The stiffness of this active cover prevented any interaction with the archwire, thereby rendering it a passive bracket system.
The Damon SL (U.S. Pat. No. 5,429,500), a passive system, was introduced a year later, in 1996. The TwinLock bracket developed by A. J. Wildman (U.S. Pat. No. 5,700,145) who also had designed the Edgelock, entered the marketplace in 1998.
A year later, the TwinLock bracket was modified and named Damon 2 (a passive system), and Damon 3 (U.S. Pat. No. 7,267,545), a hybrid passive bracket made from metal and composite resin, was designed in 2004.
BIRNIE (2008) reports that since its introduction the design of the Damon bracket has featured a passive self-ligating design, conventional ties, and a cover with a positive passive mechanism to keep it open or closed. As the bracket kept evolving, its features changed as well: it became smaller with a lower profile and rounded contours providing more comfort to patients. As a result of clearer understanding of the function of the bracket and advances in manufacturing technologies, the mechanism of the cover became safer and simpler to open and close.
In 2000, GAG introduced In-Ovation bracket (U.S. Pat. No. 6,368,105) which was bulkier than SPEED bracket and featured an active Elgiloy clip different from the SPEED nickel titanium clip whose elasticity of the material was larger.
In 2004, the passive Smartclip bracket was introduced (U.S. Pat. No. 7,686,613) while Damon 3MX was launched in 2005 and followed in 2006 by Quick Bracket by Forestadent (a German company) whose action of the clip was active.